I have an existing NVR at another site that I can monitor from my phone, I changed my parents from Voyager to One NZ a few months back. Last week my dad said the NVR isn't working on his phone when I was over, I checked on my phone and didn't work. It was working earlier that day so I said I'll see if it fixes itself later. Checked later when I was home and it was working. Went to his house and passively said its working, checked and not working again. Went off wifi and to 4g and it was working.
I know CCTV has special ports but is there anything I can check or change to make it work at his house so he doesn't burn through 4G data?